A general process for manufacturing the semiconductor chip packages includes a chip mounting step in which semiconductor chips are mounted on a substrate, a molding step in which semiconductor chips are molded with a molding resin to protect the electric connection between semiconductor chips and the substrate and a cutting step in which the molded semiconductor chips are cut into individual chips. In case of the ball grid array type semiconductor, the substrate is made by laminating a plurality of thin resin sheets on which circuit patterns are laid.
FIG. 1 shows the conventional substrate and FIG. 2 shows the conventional resin forming molds. On the surface of the substrate 100, there are provided a plurality of chip pads 20 for mounting semiconductor chips 103, and on one sides of respective chip pad 20, there are provided with resin routes 102 through which molding resin may flow. After the semiconductor chips 103 are bonded on the substrate 100, the substrate 100 is placed between the upper mold 70 and the lower mold 72, then molding resin 82 is injected by plunger 84 into the cavity 74 of molds 70, 72, whereby the semiconductor chip package is made.
But, when the resin flows along the resin routes 102, some of the resin remains and is attached on the resin routes 102 after the resin hardens. As the remaining resin may cause the defect of semiconductor chip packages, a removing process of the remaining resin(degating process) is required. When the remaining resin is removed from the resin routes 102 of the substrate 100, the inter-layer peeling may take place. In order to solve this problem, there has been provided substrates wherein a gold or other metal is plated on the resin routes 102, which make it possible to remove remaining resin easily.
However, for the gold plating of substrate, plating equipments and manpower are required, which results in higher cost of semiconductor chip packages.